1. Field of the Invention
The present invention relates to a ventilator having an optimum fan structure, and more particularly to a ventilator having an optimum fan structure that enhances the air drainage rate of the ventilator and reduces noise during operation of the ventilator.
2. Description of the Related Art
The ventilator usually comprises a fan motor that is operated at a high rotational speed, so as to drain the oily smoke contained in the kitchen outward, thereby achieving the ventilating effect. A conventional ventilator comprises a fan structure including a plurality of arc-shaped blades that are rotated by the fan motor to produce a suction force for sucking the oily smoke so as to drain the oily smoke outward. However, each of the blades has a fixed curvature, so that the suction force produced by the blades is limited, thereby decreasing the air drainage rate of the ventilator. In addition, each of the blades has a bottom formed with a right angle, thereby easily producing noise during operation of the ventilator.